1. The Field of the Invention
The present invention relates to a flexible airbag inflator. More specifically, the present invention relates to an airbag inflator with a corrugated metal housing that can be perforated to create inflation fluid exit ports, and bended without adversely affected the membrane-enclosed combustible material within the housing.
2. The Relevant Technology
Inflatable safety restraint devices, or “airbag restraints,” are mandatory on most new vehicles. Airbag restraints commonly contain a collision sensor, inflator, and an airbag or inflatable curtain. In the event of an accident, the collision sensor within the vehicle, such as an accelerometer, measures abnormal deceleration and triggers the inflator. The inflator is connected to the airbag which is typically housed in the steering wheel on the driver's side of a vehicle and in the dashboard on the passenger side of a vehicle. Airbags are normally housed in an inflated and folded condition to minimize space requirements. Upon receipt of the signal from the collision sensor, the inflator rapidly produces a quantity of inflation fluid or gas which fills the airbag and protects the passenger from harmful impact with the interior of the car.
Airbags have also been developed in response to the need for passenger protection from lateral impacts with the side of a vehicle's interior. This situation might occur when another vehicle collides with the side of the car, or when the car loses control and rolls over causing the side of car to repeatedly impact the ground. Side impact inflatable curtains are designed to prevent the head of a vehicle occupant from emerging through the window opening or from colliding with a collision surface at the side of the vehicle. The shape of the curtain generally conforms to the shape of the window area or side of the car adjacent the passenger's torso. Side inflatable curtains are typically housed in an uninflated and folded condition and attached to, or within, the roof rail of the vehicle behind a vehicle headliner.
With the ultimate premium on vehicle interior space, vehicle manufacturers are always seeking for new and creative ways to secure and house the curtain and the inflator within the vehicle. In certain circumstances, it is desirable to have the inflator conform to a curved portion of the vehicle frame. The problem with most inflators, however, is that they are not flexible. Thus, they cannot be mass produced for different vehicle applications. Accordingly, additional tooling and manufacturing is required which drives up costs. Further, with fixed and rigid inflator configurations, installation into the specific vehicle for which a known inflator is manufactured must be exact and precise. Thus, installation becomes more time consuming which drives up installation costs.
Some attempts have been made to provide a flexible inflator, but these inflators also suffer significant disadvantages. One known inflator includes a rubber housing. Often times, however, the exit ports in the rubber through which the hot inflation fluid must pass will deform, expand, or crack, under the high inflation pressure and hot expanding gasses. This can negatively affect the rate at which the inflation fluid inflates the curtain, and thus, inflation performance. Many known flexible inflators do not provide controlled diffusion of combustion pressures. Other inflators, while flexible, are not rigid enough to protect the gas generating material, which, if damaged, can also negatively affect the rate of evolving gas. Yet another problem with many flexible inflators is that they do not provide for high pressure containment for safe use in automotive applications. For example, in certain situations, it is desirable to use stored pressurized gas to create inflation fluid. Some inflators that provide flexibility, do so at the expense of being a pressure vessel.
Another problem with known inflators is that they do not account for the hot inflation gasses which could burn a passenger, even through the fabric of the curtain, during or immediately after inflation. Some known inflators may provide a heat sink, but again, these inflators sacrifice flexibility because the heat sink employed is rigid metal. Other flexible heat sinks can cause damage to the combustible materials or material seals because of burrs or exposed wires in the heat sink materials after inflation gas exits ports are pierced through the head sinks.
Thus, it would be an advancement over the prior art to provide a flexible inflator that can conform to the shape of the headliner or interior frame of a vehicle, yet won't damage the gas generating material or compromise inflation performance. It would be another advancement to provide such an inflator which has discrete exit ports that can withstand the heat and pressure of the expanding inflation fluid and not deform, thus preserving the rate of evolving gas. It would yet be another advancement to provide such an inflator that provides high pressure containment for safe use in automotive applications. It would yet be another advance to provide such an inflator with a heat sink for the inflation exiting fluid and ports that will not allow damage to the combustible material or the seal containing the combustible material.
Such an inflator is disclosed and claimed herein.